When fools gold, iron (IV) sulfide reacts with oxygen it forms iron (III) oxide and Sulfur dioxide. Need help filling out boxes ASAP!!

Acrystal that absorvd water from air is (blank)a. aqueousb. homogenousc. hygroscopicd. efflorescent

What is the percent composition of ca(oh)2? 37.7% ca, 53.0% o, and 10.3% h 45.5% ca, 38.2% o, and 16.3% h 54.0% ca, 43.0% o, and 2.7% h 64.7% ca, 27.0% o, and 8.3% h

How do i turn 2 s into one in the products